-LRB- CNN -RRB- Most airline pilots have an above average ability to compartmentalize personal problems . The cockpit is our `` safe '' place . The flight deck is a structured world of black and white . Checklists . Procedures . Standardization .

Stress from the job is an accepted part of our career . However , sometimes during the course of an airline pilot 's career , or anyone 's career for that matter , stress issues may manifest as depression . Depression is treatable . And for airline pilots , it is no longer debilitating to our livelihood . The Federal Aviation Administration now approves certain prescribed medication , allowing us to continue flying until depression is no longer a factor .

As the world learns more about Andreas Lubitz , the co-pilot on Germanwings Flight 9525 , it is readily apparent that this young man had psychiatric issues far beyond clinical depression . He reportedly was administered a series of injections to mitigate his problems , an absolute reflection on the serious nature of his illness . But Lubitz 's illness did n't just appear out of thin air . Its effects had to be apparent to others . Lubitz 's girlfriend made her concerns public knowledge -- unfortunately after events took their course .

Considering the hoops Lubitz had to jump through to have established himself as a Germanwings co-pilot , it 's curious to me how the red flags of his illness were missed . To what hoops am I referring ?

First , let 's start with his passion for gliders . Glider flying is one of the purest forms of aviation . Although it is mostly an individualistic endeavor , the sport involves teamwork . Interaction among fellow enthusiasts is paramount to both enjoyment and safety . I 'm a glider pilot . Participation among the members of my club uncovers the personalities and idiosyncrasies of each pilot . Behaviors not quite conducive to the activity are readily apparent .

Second , Lubitz had to compete successfully in a selection process just to have the opportunity to train through Lufthansa 's flight program , a requirement of Germanwings employment . The selection process is most likely highly competitive , requiring above-average aptitude . Is the selection process flawed to the extent that a serious mental disorder would go unnoticed ? Regardless , the process had to be a stressful experience .

Opinion : Germanwings and the stigma of mental illness

Once accepted into the flight program , a rigorous training period began . For primary training , Lufthansa utilizes an ab initio -LRB- from the beginning -RRB- program based at a facility the airline owns in Goodyear , Arizona , near Phoenix . The training is geared toward a multi-crew pilot license , or MPL , recognized by the International Civil Aviation Organization . The purpose of an MPL is to funnel airline pilot candidates having little or no flight time into the right seat as first officers . Countries that do n't have the luxury of selecting from a large pool of experienced pilots use this license .

Airline pilots in the United States are not licensed in this manner , requiring as much as 1,500 hours to qualify as a co-pilot . This is a fairly recent change in FAA regulations , initiated as a result of the 2009 Colgan Airlines crash in Buffalo , New York . Lubitz had barely over 600 hours of flight time when he committed his act of horror . As a 21-year-old flight instructor , I had that much flight time ; it hardly qualified as a lot of experience .

As with all of the MPL programs , the training involves an intense period of airline-specific instruction . And to add insult to injury , candidates are not paid during the training until such time as they pass a final check ride . Regardless , the cost is borne by the student to the tune of about $ 76,000 .

Using both actual flight experience in a single-engine airplane and simulator time , the student receives about 250 hours of training . It is a period of almost constant supervision . Aside from observing and checking performance criteria , would n't at least one instructor have noticed behavioral issues in such an intense environment ? And would n't a fellow trainee have noticed also ?

According to reports , Lubitz took a leave from his training -- a very untypical behavior . Was that not in and of itself a red flag ? Would n't a manager in Lufthansa 's flight department consider it prudent to reconsider a candidate with an indication of potential issues ? After all , the selection process was most likely highly competitive , with other qualified candidates readily available .

Once the primary training in Arizona was complete , Lubitz would have returned to Germany and completed more specific schooling on the Airbus A320 he was about to fly . Again , no one observed issues . But even more curious , according to reports , Lubitz disclosed a diagnosis of previous depression to Lufthansa .

Over the course of a career , an airline pilot spends thousands of hours sharing the confined space of the cockpit with colleagues . Even if we have never flown with a particular individual , experience allows us the intuition to know when something is n't quite right . That determination can be made through performance observation of typical routines , or perhaps through a simple conversation . In that regard , I find it difficult to believe that none of Lubitz 's colleagues made a less than positive assessment at some point in time .

As supplemental background , Germanwings had been established as the low-cost , alter ego carrier of Lufthansa . Depending upon a pilot 's monthly flight time , salary for pilots can be as much as 20 % lower than the mainline carrier . In addition , more days on duty were part of a Germanwings crew member 's schedule . Apparently as late as March 20 , Lufthansa pilots had been on strike , one of the main disputes being an early retirement option and less desirable working conditions for new hires . Perhaps enough of a disparity existed for Germanwings pilots such that medical leave benefits would not have covered Lubitz 's absence .

Regardless , all of these factors combined to add a perfect storm of stress to one sick 27-year-old man . The world knows the end result . It just seems to me that this was an accident waiting to happen . Could it have been prevented ? Well , this is the primary purpose of accident investigation : Never allow the same tragedy to occur again .

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Les Abend : There were likely warning signs during the co-pilot 's training

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He says Andreas Lubitz had to go through many challenges to qualify to be a co-pilot